The legislation would also review the air quality standards every 10 years, instead of the current five years, and require the EPA to consider technological feasibility and how pollution from other countries affects US air quality when revising the standard.

While everyone agrees the 2015 ozone standard is one of the EPA’s most expensive rules — the EPA estimated lowering allowable ambient ozone concentrations from 75 parts per billion to 70 parts per billion would cost $2 billion — the agency says the public health and environmental benefits outweigh the costs.

The agency puts the benefits at $3.1 billion to $8 billion.

Manufacturers, however, put the price of implementation much higher: a National Association of Manufacturers study found that setting an ozone standard of 65 parts per billion would cost $1.7 trillion dollars by 2040. While the EPA didn’t set a 65 parts per billion limit, its original proposal considered strengthening the air quality standards to within a range of 65 parts per billion to 70 parts per billion.

Last year, the National Association of Manufacturers joined a lawsuit challenging the 2015 ozone standard. “This could be one of the most expensive regulations in history, creating significant barriers to manufacturers’ ability to open new plants and expand existing operations,” said NAM senior vice president and general counsel Linda Kelly in January 2016.

The industry group praised the recent introduction of the bipartisan Ozone Standards Implementation Act of 2017 (S. 263/H.R. 806), which is said “offers a balanced approach that ensures continued air-quality improvements, while giving states and manufacturers the flexibility necessary to limit some of the economic growth restrictions that exist under the current regulation.”